package org.bug2222.reggie.filter;

import com.alibaba.fastjson.JSON;
import lombok.extern.slf4j.Slf4j;
import org.bug2222.reggie.common.BaseContext;
import org.bug2222.reggie.common.R;
import org.springframework.util.AntPathMatcher;

import javax.servlet.*;
import javax.servlet.annotation.WebFilter;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import java.io.IOException;

/**
 * 检查用户是否已经完成登录
 */
@WebFilter(filterName = "loginCheckFilter",urlPatterns = "/*")
@Slf4j
public class LoginCheckFilter implements Filter {
    public static final AntPathMatcher PATH_MATCHER = new AntPathMatcher();

    @Override
    public void doFilter(ServletRequest servletRequest, ServletResponse servletResponse, FilterChain filterChain) throws IOException, ServletException {

        HttpServletRequest request = (HttpServletRequest) servletRequest;
        HttpServletResponse response = (HttpServletResponse) servletResponse;

        //1、获取本次请求的URI
        String requestURI = request.getRequestURI();
        log.info("拦截到请求{}", request.getRequestURI());
        //放行的路径
        String[] urls = new String[]{
                "/employee/login",
                "/employee/logout",
                "/backend/**",
                "/front/**",
                "/common/**",
                "/user/sendMsg",
                "/user/login",
        };

        //2、判断本次请求是否需要处理
        boolean check = check(urls,requestURI);

        //3、如果不需要处理，放行
        if (check){
            log.info("{}不需要处理", request.getRequestURI());
            filterChain.doFilter(request,response);
            return;
        }
        //4-1、判断登录状态，如果登录，放行
        if (request.getSession().getAttribute("employee")!=null){
            log.info("用户已登录，ID为{}", request.getSession().getAttribute("employee"));

            log.info("线程ID为{}",Thread.currentThread().getId());

            Long empId = (Long)request.getSession().getAttribute("employee");
            BaseContext.setCurrentId(empId);

            filterChain.doFilter(request,response);
            return;
        }
        //4-2、判断登录状态，如果登录，放行
        if (request.getSession().getAttribute("user")!=null){
            log.info("用户已登录，ID为{}", request.getSession().getAttribute("user"));

            log.info("线程ID为{}",Thread.currentThread().getId());

            Long userId = (Long)request.getSession().getAttribute("user");
            BaseContext.setCurrentId(userId);

            filterChain.doFilter(request,response);
            return;
        }
        //5、如果未登录则返回未登录结果，通过输出流方式向客户端页面响应数据
        log.info("用户未登录");
        response.getWriter().write(JSON.toJSONString(R.error("NOTLOGIN")));
        return;
    }

    /**
     * 路径匹配，检查本次请求是否要放行
     *
     * @param requestURI
     * @return
     */
    public boolean check(String[] urls, String requestURI) {
        for (String url : urls) {
            boolean match = PATH_MATCHER.match(url, requestURI);
            if (match) return true;
        }
        return false;
    }
}
